Overvoltage protection devices can be used to protect electronic circuits and components from damage due to overvoltage fault conditions. These overvoltage protection devices may include metal oxide varistors (MOVs) that can be connected between the circuits to be protected and a ground line. MOVs have current-voltage characteristics that allow them to be used to protect such circuits against catastrophic voltage surges. These devices may utilize a thermal link that melts during an overvoltage condition to contribute to the formation of an open circuit. In particular, when a voltage is applied to an MOV that is larger than the nominal or threshold voltage of the MOV, then a current can flow through the MOV that generates heat that can cause the thermal link to melt. Once the link melts, an open circuit can be created which prevents the overvoltage condition from damaging the circuit to be protected.
These conventional circuit protection devices, however, do not provide an efficient heat transfer from the MOV to the thermal link, thereby delaying response times. In addition, MOV devices have relatively high inductance characteristics, which may degrade performance in the presence of fast overvoltage transients. Moreover, conventional circuit protection devices are often complicated to assemble and require too many components to be used effectively in certain applications such as in Light Emitting Diode (LED) protection. Accordingly, it will be appreciated that improvements are desirable over conventional circuit protection devices employing metal oxide varistors.